Hydraulic clutch cnc master cylinder

[dcstang67]

I currently have a T5Z with a Ram Powergrip HD clutch installed. Even with the hydraulic pedal it is still pretty stiff. It really givees my leg a workout in traffic. The master is a CNC 3/4" cylinder. The slave is a CNC Push style 305. I would like to go bigger with the master to make the pedal a little easier. Should I go up to 7/8" or 1"?

 

[zookeeper]

If the pedal is too stiff, you need a smaller bore, not larger, to make the pedal effort lighter.

 

[C0V3R]

Or you need to mount the clutch linkage pin closer to the upper pivot to get more leverage

 

[jikelly]

Or you need to mount the clutch linkage pin closer to the upper pivot to get more leverage

Sounds like you're using the same master slave combo that I have in my stang. Leverage is likely the answer. My pedal is fairly easy to depress, but it took me a while to find the best pivot point to get the pedal throw and effort close. I had to compromise a bit. Using on of those aftermarket pedal assembles would have probably been optimal, but who know what I'd have had to do to make one fit under the dash.

A larger master will be displacing a larger amount of fluid as the pedal is depressed. I thought about putting one in my car just to reduce the amount of travel in the pedal. I decided to just live with what I'd already put together.

 

[dcstang67]

If I went with a smaller master to make the pedal effort easier then the the throw of the slave would be smaller right? Looks like I might have to raise the linkage point on my pedal. Maybe fabricat a wedge shaped spacer to go between the master and the firewall to mimic the angle on the JMC master cylinders.

 

[gjz30075]

If I went with a smaller master to make the pedal effort easier then the the throw of the slave would be smaller right?

No. The stroke of the master will be longer to accomplish the same work. ie, if the clutch disengages/engages at half pedal currently, for instance, then with a smaller master you might get disengage/engagement at 3/4's of the way down instead. Obviously, you can only go 'so much' smaller before you run out of travel to accomplish the same work. You might want to try a 5/8" master. We did this on my friends car. Went from a 3/4" to 5/8" and it made a great difference in pedal feel. I think we had to 'preload' the throwout bearing against the fingers to get disengagement but it really works good.